CVE-2022-49423
📋 TL;DR
This CVE describes a NULL pointer dereference vulnerability in the Linux kernel's rtla (Real-Time Linux Analysis) tools. If exploited, it could cause kernel crashes or denial of service on systems using these tracing tools. The vulnerability affects Linux systems with specific kernel versions that include the vulnerable rtla components.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash and denial of service, potentially requiring physical or remote reboot.
Likely Case
Application crash when using rtla tools (osnoise_hist, osnoise_top, timerlat_hist, timerlat_top) with specific conditions triggering the NULL pointer dereference.
If Mitigated
No impact if rtla tools are not used or if the vulnerable code paths are not executed.
🎯 Exploit Status
Exploitation requires local access and ability to execute rtla tools with specific parameters to trigger the NULL pointer condition.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions with commits 2a6b52ed72c822b5ee146a6a00ea66614fe02653 and b0f1c686baff74d5df10f2f46670ef4e24a75756
Vendor Advisory: https://git.kernel.org/stable/c/2a6b52ed72c822b5ee146a6a00ea66614fe02653
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution. 2. Reboot system to load new kernel. 3. Verify rtla tools work without crashes.
🔧 Temporary Workarounds
Disable rtla tools
linuxRemove or restrict execution permissions for rtla tools to prevent exploitation
chmod -x /usr/bin/rtla
rm /usr/bin/rtla
Restrict user access
linuxLimit which users can execute rtla tools using sudoers or file permissions
chmod 750 /usr/bin/rtla
chown root:trustedgroup /usr/bin/rtla
🧯 If You Can't Patch
- Remove rtla package entirely if not needed for system functionality
- Implement strict access controls to prevent unauthorized users from executing rtla tools
🔍 How to Verify
Check if Vulnerable:
Check if rtla is installed and check kernel version against distribution security advisoriesCheck Version:
uname -rVerify Fix Applied:
Execute rtla tools with various parameters and monitor for crashes or kernel panics📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages
- System crash/panic logs
- rtla process crashes in system logs
SIEM Query:
process.name:"rtla" AND (event.type:"crash" OR log.level:"panic")